Name: ac source conversion in circuit analysis
Uploaded: 2024-04-11T12:48:49.000Z
Duration: 1 min 11 s
Channel: JoVE

Considérons un circuit composé d’une source de courant et d’une combinaison de résistances, de condensateurs et d’inductances avec des valeurs d’impédance connues.
L'objectif est d'utiliser la technique de transformation de source pour déterminer la chute de tension aux bornes de la branche la plus à droite du circuit.
En utilisant la transformation de source, une source de courant en parallèle avec une impédance peut être convertie en une source de tension en série avec la même impédance ou vice-versa.
En appliquant la loi d'Ohm, la tension de la source est calculée. Cette valeur peut alors être exprimée en termes de phaseur.
Dans le circuit transformé, l’impédance est en série avec la source de tension, ainsi que les deux autres éléments de la branche supérieure. L’impédance série équivalente est obtenue.
Maintenant, la technique de transformation de source est à nouveau appliquée pour reconvertir la source de tension en une source de courant.
Ensuite, l’impédance de la nouvelle combinaison parallèle est obtenue, qui est utilisée pour transformer la source de courant en une source de tension.
Enfin, la règle de division de la tension détermine la chute de tension aux bornes de la branche la plus à droite.

transformation de source pour les circuits ca

Le processus de transformation de source dans le domaine fréquentiel implique la conversion d'une source de tension, positionnée en série avec une impédance, en une source de courant parallèle à une impédance, ou inversement. Il est essentiel de maintenir les relations suivantes lors de la transition d'un type de source à un autre. <img alt="Equation1" src="/files/ftp_upload/15112/15112_PT_Equation_1.svg" style="text-align: center; height: 16px;"> <img alt="Equation2" src="/files/ftp_upload/15112/15112_PT_Equation_2.svg" style="text-align: center; height: 40px;"> Afin de déterminer la tension inconnue pour un circuit composé d'une source de courant et d'un ensemble de résistances, de condensateurs et d'inductances, chacun avec son impédance connue distincte, une série d'étapes est suivie. Initialement, la source de tension est convertie en source de courant et les valeurs du courant source (Is) et de l'impédance (Zs) sont établies. Par la suite, la transformation de la source de courant en source de tension entraîne un circuit différent. A partir de ce circuit dérivé, la tension source (Vs) est calculée en utilisant les valeurs précédemment déterminées. Enfin, en appliquant la règle de division de tension, la tension inconnue aux bornes de la résistance peut être identifiée.

Transformation de source pour les circuits CA

Considérons un circuit composé d’une source de courant et d’une combinaison de résistances, de condensateurs et d’inductances avec des valeurs d’impédance connues.
L’objectif est de...

Education

Enseignement

JoVE Core

Electrical Engineering

Génie électrique

Unit 1

Unité 1

AC Circuit Analysis

Analyse des circuits CA

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

Source Transformation for AC Circuits

ac source conversion in circuit analysis

AC source conversion is a circuit analysis method used in the frequency domain. It changes a voltage source in series with an impedance into a current source in parallel with the same impedance, or it converts a current source back into a voltage source. The source values must keep the correct relationship during each change.

This method helps solve for an unknown voltage in a circuit that includes a current source and components such as resistors, capacitors, and inductors. Each of these parts has a known impedance. The circuit is handled in steps so the final voltage can be found more easily.

First, the voltage source is converted into a current source. The source current, Is, and the source impedance, Zs, are identified. Next, the current source is changed back into a voltage source, which gives a new circuit form. From that derived circuit, the source voltage, Vs, is calculated. The final unknown voltage across the resistor is then found with the voltage division rule.

AC Source Conversion in Circuit Analysis

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source transformation for ac circuits

AC source conversion is a circuit analysis method used in the frequency domain. It changes a voltage source in series with an impedance into a current source in parallel with the same impedance, or it converts a current source back into a voltage source. The source values must keep the correct relationship during each change. This method helps solve for an unknown voltage in a circuit that includes a current source and components such as resistors, capacitors, and inductors. Each of these...

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key terms and concepts

Learn how AC source conversion turns voltage sources into current sources and back again to find unknown voltage with impedance and voltage division.

AC Source Conversion in Circuit Analysis | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

electrical engineering

AC Source Conversion in Circuit Analysis

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